/*
 * Copyright (c) 2017-present, CV4J Contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.cv4j.core.spatial.conv;

import com.cv4j.core.datamodel.ImageProcessor;
import com.cv4j.core.filters.BaseFilter;

import java.util.Optional;
import java.util.Random;

/**
 * sapnoise过滤器
 *
 * @author dev
 * @date 2021/07/22
 */
public class SAPNoiseFilter extends BaseFilter {
    private float precent;

    /**
     * sapnoise过滤器
     */
    public SAPNoiseFilter() {
        precent = 0.01f;
    }

    /**
     * 得到Precent
     *
     * @return float
     */
    public float getPrecent() {
        return precent;
    }

    /**
     * 设置Precent
     *
     * @param precent Precent
     */
    public void setPrecent(float precent) {
        this.precent = precent;
    }

    /**
     * 做的过滤器
     *
     * @param src src
     * @return {@link Optional<ImageProcessor>}
     */
    @Override
    public Optional<ImageProcessor> doFilter(ImageProcessor src) {
        Random random = new Random();
        int numOfSalt = (int) (width * height * precent);
        int row = 0;
        int col = 0;
        int index = 0;
        for (int i = 0; i < numOfSalt; i++) {
            row = getPosition(0, height, random);
            col = getPosition(0, width, random);
            index = row * width + col;
            RED[index] = (byte) 255;
            GREED[index] = (byte) 255;
            BLUE[index] = (byte) 255;

            row = getPosition(0, height, random);
            col = getPosition(0, width, random);
            RED[index] = (byte) 0;
            GREED[index] = (byte) 0;
            BLUE[index] = (byte) 0;
        }
        return Optional.ofNullable(src);
    }

    /**
     * 得到的位置
     *
     * @param min 最小值
     * @param max 马克斯
     * @param random 随机
     * @return int
     */
    private int getPosition(int min, int max, Random random) {
        return random.nextInt(max - min);
    }
}
